Finally, we would like to compare our model result with the model calculations or extractions from other groups [1]}, [2]}, [3]}, [4]}.
In Ref. [2]}, the sea quark Sivers functions are calculated with the chiral model.
In that model, the Sivers function of \(\bar{u}\)  is negative and that of \(\bar{d}\)  is positive.
In addition, the size of the first \(k_T\)  moment timed with \(x\)  is 0.004 at most at the scale \(Q=0.63\)  GeV.
In Ref. [3]}, the Sivers functions including those of \(\bar{u}\)  and \(\bar{d}\)  are obtained by assuming a connection between generalized parton distribution \(E\)  and the Sivers function and by fitting the SSA data in SIDIS process.
In this study, the size of \(xf_{1T}^{\perp (1)}\) (x) for \(\bar{u}\)  and \(\bar{d}\)  is 0.006 at most, which is similar to the results in Ref. [2]}; However, their signs are opposite to those in Ref. [2]}, and the \(x\) -dependence are also different.
A recent extraction [1]} which implements TMD evolution shows that the sign of the sea quark Sivers function is negative (In this extraction the \(\bar{u}\)  and \(\bar{d}\)  quarks are not distinguished).
This result is consistent with our model calculation.
In general, the size of our results is similar with those in Refs. [2]}, [3]}, [4]}, [1]}.
Hopefully, the reasons for these differences can be checked through theoretical and experimental analysis in the future.
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